pcm wiring help

[dynamite40]

hi all hope everybodys safe and well
im looking for some help in wiring an old 7s LT-POWER pcm to a 7s5p battery
i have searched the internet but cannot find any details on this hope somone can help
all the best

 

[vfr400]

Thick blue (CH-) is charge socket Negative. the black next to it (B-) is the output negative to the terminal. The other thick black (DS-) goes to the cell-pack negative. B0 goes to the same point, B1 to the top of cell 1, B2 top cell2, etc.

The red positive from the cell-pack goes direct to the terminal and the charge positive will be joined to the same point on the cell-pack and goes to the charge socket positive.

Fuses on the charge positive and output positive are optional.

 

[dynamite40]

thank you really appreciate your help
im new to all this if i get stuck do you mind if i ask for your help again
stay safe all the best

 

[Nealh]

Unlike you Dave, did you check the pcb board pads ?
The reverse side markings B-/CH on the case are misleading.

If one looks at the pcb board it self and the soldered wire pads.
Blue on board is the B- and is soldered to battery group B-, the thin black sense wire is B0 so solders to the same cell group.
Black wire next to Blue is CH on the board so is wired to the charge point/connector (this Black is thinner)
DS is discharge so directly to the battery discharge connector, it is a thicker awg wire then the other Black CH.

Sense wires are Red thin is B1, thin Blue B2, White B3, Green B4, Yellow B5, Black B6 and Red B7.

Make your V+ solder connections first so discharge connector Red to B7 cell group and the charge connector Red .

Solder DS thicker Black to discharge connector.
Solder B- slightly thinner Black to cell group B-/B0.
Finally solder the sense wires BC0 to B- along with the thick Black wires, BC1 - BC7 to the relevant v+ the cell groups. Check the cell group voltages before soldering the wires as you go along to make sure they are soldered to the correct cell groups.

 

[dynamite40]

Many thanks before I do anything I will draw a diagram first so you all can have a look see if it's right

 

[vfr400]

Neal's right. I got the designations right but the blue is the cell-pack negative and the medium black is the charge negative.

 

[dynamite40]

thank you all

 

[dynamite40]

Thanks for your help so far really appreciate it
Would it be possible to take a quick look at this crude diagram to see if I have things right
Once again many thanks

 

[vfr400]

That's all correct.

 

[dynamite40]

Thank you Will let you know how I get on

 

[Nealh]

All good.
If one wishes, the sense wires can be soldered on the buss strip between +& -.
Depending how the B- & V+ discharge wires re connected. If you want optimal current through the first and last cell group, solder each wire to the middle cell of the group so that current flows in from the ends rather then from one end to the other.

 

[dynamite40]

Neal vfr400 thanks guys so much for your help my bikes now back up and running well pleased
To you both and to all on pedelecs Have a fantastic Christmas stay safe

 

[Nealh]

Yes, Merry Christmas every one.